Rock wall slicer



June 4, 1968 J. A. KNUPKE ROCK WALL SLICER 2 Sheets-Sheet 1 Filed Feb.28, 1966 @waa lll l-- l lill. l... l .III

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June 4, 1968 1. A. KNUPKE ROCK WALL SLICER 2 Sheets-Sheet 2 Filed Feb.23, 1966 INVENTOR. JA/w55 A, KMU/2K5 OPA/PY United States Patent O3,386,522 ROCK WALL SLICER James A. Knupke, Corpus Christi, Tex.,assignor to Continental Oil Company, Ponca City, Okla., a corporation ofDelaware Filed Feb. 28, 1966, Ser. No. 530,447 9 Claims. (Cl. 175-311)ABSTRACT F THE DISCLOSURE An apparatus for obtaining rock samples fromthe wall of a well bore wherein the samples are sliced from said wall byconverging saw blades and collected in a plurality of sample -chambersof said lapparatus so as to segregate said samples on the basis of thedepth of said apparatus in said well bore.

This invent-ion relates to a tool for obtaining rock samples from thewall of a well bore. More particularly, the invention relates toapparatus for severing a continuous rock slice from the wall of aborehole over a considerable vertical distance, and for collecting andclassifying portions of the rock slice.

Data derived from samples of rock obtained from a well bore during adrilling operation are of great value to the geologist in theexploration for oil and gas. D-ue to changes in the economics of welldrilling, and to recent innovations in the apparatus used in thistechnology, the physical character and the chemical environment of rocksamples recovered from wells have been detrimentally altered so as torender it increasingly ditlicult for the geologist to derive an optimumamount of useful information from such samples.

The present invention provides an improved apparatus for obtaining rocksamples from the wall of a well bore over a long interval and in arelatively undisturbed state. Broadly described, the apparatus comprisesa housing supporting a pair of saw blades which are mounted inconverging planes and have converging cutting edges located outside thehousing. The housing contains means for driving the saws in a cuttingmotion, and a sample receiving compartment disposed below the sawblades, which compartment has a plurality of retractable partitionmembers supported therein in vertically spaced relation. The housingalso encloses actuating means drivingly connected to the severalretractable partition members for individually and selectively movingthese members from a rst position, in which they extend across andpartition the sample receiving compartment into a plurality of samplechambers, to a second position, in which they are retracted to anon-obstructing position permitting the rock samples to pass freelyfro-rn the top to the bottom of the compartment. Finally, a gougingprotuberance is provided on the outside of the housing directly belowthe saw blades and adjacent an opening'in the wall of the housing whichcommunicates with the sample receiving compartment.

In operating, the rock wall Slicer of the invention produces twoconverging saw cuts in the wall of the Well bore adjacent the housing,thus forming a Wedge-shape slice of rock which is retained in placeafter penetration of the saw blades by a narrow neck of rockcorresponding in thickness to the distance which separates the sawblades at their points of greatest convergence. As the tool is pulledupwardly -in the hole, the gouging protuberance breaks out t-he sliceand directs the broken slices into the sample receiving chamber in thehousing. The rock samples thus collected may be segregated or classifiedin correlation to the depth of the tool by selectively act-uating theretractable partition members so that, at different "ice times, thesamples are channeled into different chambers within the samplereceiving compartment.

An important object of the invention is to provide an improved apparatusfor collecting relatively undisturbed samples of rock from a well bore.

An additional object of the invention is to provide a rock wall slicerfor collecting slices of rock from the wall of a well bore in a sequencewhich allows identification of the depth interval from which the slicesare cut.

Another object of the invention is to provide an eilicient tool forremoving slices of rock from the wall of a well borehole over a longinterval of the borehole in a relatively continuous operation.

A further object of the invention is to provide a rock wall slicer foruse in collecting rock samples from wells, which slicer is relativelyeconomically constructed and is characterized by a long and trouble-freeoperating life.

In addition to the foregoing described objects and advantages,.additional objects and advantages will become apparent as the followingdetailed description is read in conjunction with the accompanyingdrawings which illustrate the invention.

In the drawings:

FIGURE 1 is a view in elevation of the rock wall slicer tool of theinvention as it appears in a well bore.

FIGURE 2 is a view in elevation of the tool illustrated in FIGURE 1, butshowing the tool as it appears when rotated from the FIGURE 1 position.

FIGURE 3 is a vertical sectional view taken through the center of therock wall slicer tool of the invention.

FIGURE 4 is a horizontal sectional view taken along line 4-4 of FIGURE1.

FIGURE 5 is an enlarged vertical sectional view of the lower portion ofthe tool illustrating the manner in which the retractable partitionmembers are utilized to form a plurality of sample chambers for thepurpose of segregating the rock samples according to the depth at whichthey are collected.

Referring now to the drawings, which illustrate an exemplary embodimentof the invention, reference numeral 10 designates `a. well boreextending downwardly in the earth 12. The rock wall Slicer tool of thepresent invention is designated generally by reference numeral 14, andis shown suspended on a multi-strand wire cable 16 which surrounds andprotects a plurality of electrical conduits as hereinafter described.The rock wall slicer tool 14 includes a generally cylindrical housing 18which is of slightly smaller diameter than the mean diameter of theborehole and is provided with a bottom wall 20 as best illustrated inFIGURE 3.

Mounted on the outside of the housing and spaced approximately in acircumferential direction therearound from each other are a pair ofstabilizer elements 22 which can be constructed of spring metal andwelded or otherwise suitably secured at each end to the housing 18. Thestabilizer springs 22 are each also spaced about 120 around the housing18 from a pair of elongated, vertically extending slots 24 located inthe upper portion of the housing, and provided for the accommodation ofa pair of generally circular saw blades 26. Disposed centrally betweenand below the slots 24 is a sample receiving slot 27 which is positionedimmediately over a ared gouging protuberance 28 which is mounted on theoutside of the housing 18 and tapered to a sharp point for a purposehereinafter described. A bracket 30 is located inside the housing 18 andsecured to one wall thereof, and a pair of electric motors 32 aremounted on the bracket and are drivingly connected through suitablegearing and shafts to the saw blades 26 in the manner best illustratedin FIGURE 3. As will be noted in referring to FIGURE 3, the saw blades26 are mounted convergently so as to define an angle of about 60. Theouter portions of the saw blades project through the slots 24, and in apreferred embodiment of the invention, converge to within about 1/l-inchof each other.

A sample receiving compartment 35 which, in the illustrated embodiment,takes the form of a large cylindrical shell resting upon the bottom 20of the housing 18, is positioned inside the housing and below the motors32 in alignment with the sample receiving slot 27 above the gougingprotuberance 28. A plurality of disc-shaped, retractable partitions 38having a diameter substantially equal to the diameter of the samplereceiving compartment 36 are rotatably mounted on shafts 40 which eX-tend diametrically through the compartment 36 and are spaced verticallyfrom each other therein. The retractable partitions 38 are keyed to theshafts 48 which are in turn journaled in the walls of the compartment36. A plurality of electric motors 42 are drivingly connected to theshafts 40 and are mounted on the side of the cornpartment 36 between thecompartment and the internal wall of the housing 18. Suitable electricalleads 44 and 46 extend from the motors 42 and 32, respectively, upwardlythrough the wire cables 16 to the surface where they are connected tosuitable control switches and a source of electrical power.

OPERATION For the purpose of obtaining the sample of rock from the wallof the borehole, the rock wall slicing tool 14 is lowered in theborehole to a depth at which it is located slightly below the zoneswhich are to be sampled. The saw blades 26 are then actuated byenergizing the motors 32, and the blades cut into the wall of theborehole 10 adjacent the tool 14 in the manner illustrated in FIGURE 4.Preferably, the diametric dimension and the position of the blades 26are such that each blade cuts into the wall of the borehole to a depthof about onequarter inch. The narrow slice of rock 50 thus developed isheld in place by a small neck at the back thereof which is preferablyabout 1/lg-inch in thickness, the distance which separates the sawblades at their point of closest convergence. By permitting the neck toretain the rock slice 50 on the wall until it is gouged out by thegouging protuberance 28, the sample is prevented from falling down inthe annulus between the tool and the wall of the borehole.

The rock wall slicing tool 14 is slowly pulled upwardly in the boreholeand, as it moves, the saw blades cut in f straight lines upwardly in thewall as a result of the housing 18 being forced into abutting contactwith the wall of the borehole by the stabilizers 22. The gougingprotuberance 28, which is preferably set about 21/2 inches below ahorizontal line interconnecting the center of the saw blades, breaks outthe rock slice formed by the saw blades as the tool moves upwardly inthe hole. The slices which are thus gouged out of the wall by thegouging protuberance 28 fall through the slot 27 and into the samplereceiving compartment 36.

As the tool 14 moves upwardly in the borehole 10, successivelytraversing different intervals of the subsurface structure surroundingthe borehole, the electric motors 42 are consecutively energized torotate the retractable portions 38 from the vertically aligned positionsshown in FIGURE 3 to the horizontally extending, partitioning positionsin which the lowest partition 38 is shown in FIGURE 5. Thus, a pluralityof chambers are sequentially established within the sample receivingcompartment 36 as the rock wall slicing tool 14 moves upwardly in thehole. Each of the chambers will thus receive and contain slices of rockcorresponding to a given interval of borehole traversed by the tool.When the tool 14 has reached the surface, the samples may be removedfrom the several chambers by actuating the motors 42 in reverse sequenceto open up the chambers and, in this manner, the slices of rock aresegregated and classified automatically during the sampling operation.The bottom plate 20 can be made removable by threadedly connecting it tothe housing 18 as shown in FIGURES 3 and 4 to further facilitate theremoval of the rock slices.

The rock wall slicing device 14 constructed as described can be used fordrilling wells in hard rock sections. The best results are obtained withthe tool in long, indurated sections where the hole is in gauge. Therock wall slicing tool may be run in the hole either during the drillingoperation at times following the pulling of the drill bit, or may beemployed upon the completion of drilling in theevent that very littleevaluation is needed during drilling. The tool is simple, compact andrelatively inexpensive in its construction, and can efficiently providerelatively undisturbed representative rock samples for geologicalsurveys and data accumulation in all types of well drilling operations.

Although a specific embodiment of the invention has been hereindescribed in order to provide an example to those skilled in the art ofthe manner in which it is to be constructed, it is to be understood thatvarious innovations and changes can be made in the depicted anddescribed structure without departure from the basic principles whichunderlie the invention. As an example of a change of this type, thestabilizers 22 mounted on the outer surface of the housing 18 can bemade retractable so as to minimize the possibility of sticking the toolin well bores. Also, other arrangements for mounting in the housing 18,the electric motors 32 used to drive the saw blades, could be employedeffectively in constructing the rock wall slicing tool. All such changesand modifications which continue to rely on the basic principles hereinset forth are deemed to be circumscribed by the spirit and scope of theinvention except as the same is necessarily limited by theappendedclaims or reasonable equivalents thereof.

What is claimed is:

1. A rock wall slicing tool comprising:

a housing having an upper end, a lower end and at least one side wall;

a pair of saw blades supported in said housing and occupying convergingplanes, said blades having convergent edges located outside said housingand to one side thereof;

means in said housing drivingly connected to said saw blades foractuating said blades;

a gouging protuberance mounted on the side Wall of the housing below theconvergent edges of the saw blades;

a sample receiving compartment in said housing below said protuberanceand communicating with an opening in the side wall of said housingbetween the protuberance and the convergent edges of the saw blades; and

means in said sample receiving compartment for partitioning saidcompartment into a plurality of chambers.

2. A rock wall slicing tool as dened in claim 1 wherein said means foractuating said blades comprises an electric motor drivingly connected toeach of said blades.

3. A rock wall slicing tool as defined in claim 1 wherein said means forpartitioning said compartment comprises:

a plurality of retractable partition members each movably mounted insaid compartment for movement between partitioning and non-partitioningpositions; and

means for individually actuating each of said partition members.

4. A rock wall slicing tool as defined in claim ,1 and furthercharacterized to include at least one stabilizer element mounted on theoutside of the side wall of said housing on the opposite side of saidhousing from the convergent edges of said saw blades.

5. A rock wall slicing tool as claimed in 4claim 1 and furthercharacterized to include a removable bottom plate threaded into thelower end of said housing below said sample receiving compartment andforming the bottom of said sample receiving compartment.

6. A rock wall slicing tool as claimed in claim 1 wherein said sawblades are circular in configuration and occupy planes which converge atan angle of about 60 to each other.

7` A rock wall slicing tool as dened in claim 3 wherein said means forindividually actuating each of said partition members comprises anelectric motor drivingly connected to each of said partition members.

8. A rock wall slicing tool as defined in claim 3 wherein each of saidretractable partition members is of discshaped coniguration and saiddisc-shaped partition members are mounted for rotation about horizontalaxes extending across said compartment and spaced vertically therein.

9. A rock wall slicing tool comprising:

a generally cylindrical housing having an upper end, a

lower end and at least one side wall;

a pair of circular saw blades supported in said housing and occupyingconverging planes extending at an angle of about 60 to each other, saidblades having convergent edges located outside said housing and to oneside thereof;

motors in said housing drivingly connected lto said saw blades foractuating said saw blades upon energization of said motors;

a cable connected to said housing at the upper end thereof;

electrical leads to said motors enclosed in said cable;

a gouging protuberance mounted on the side wall of the housing below theconvergent edges of the saw blades;

a generally cylindrical sample receiving compartment of lesser diameterthan said housing disposed in said housing below said gougingprotuberance and communicating with an opening in the side wall of saidhousing between the protuberance and the convergent edges of the sawblades;

a plurality of shafts extending diametrically across said samplereceiving compartment and vertically spaced from each other therein;

disc-shaped partition members mounted on each of said shafts forrotation with said shafts about a horizontal axis, said disc-shapedpartition members having a diameter substantially equal to the insidediameter of said sample receiving compartment whereby said disc-shapedpartition members may be rotated on their respective shafts to positionsin which said partition members occupy substantially vertical planes andto positions in which said partition members occupy substantiallyhorizon-tal planes and thus partition said sample receiving compartmentinto a plurality of chambers; and

an electric motor outside said sample receiving compartment anddrivingly connected to each of said shafts for individually andselectively actuating each of said partition members to partition saidsample receiving compartment and form a plurality of chambers therein.

References Cited UNITED STATES PATENTS 2,544,728 3/1951 Salford 175-3112,5 85,3 69 2/ 1952 Caruthers 175--276 2,698,733 l/l955 Schlumberger166-3 X 2,826,077 3/ 1958 Walker 175--311 X 3,173,500 3/1965 Stuart175-77 CHARLES E. OCONNELL, Primary Examiner.

NILE C. BYERS, IR., Examiner.

